This item is sold as KIT. SMD parts are soldered to PCB, THT parts have to be soldered by customer. All needed parts included in KIT.
This card adds following functionalities to CMM2: USB mouse (HT chip) including wireless, Atari joystick, Nunchuck port
Schematic can be found here: schematic REV A v03
Instruction, code can be found on Github: CMM2 Expansion Card Mouse Joy